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Weeds cause serious yield losses in sunflower production. The most common methods for weed control are herbicide application and mechanical hoeing. The objective of this study was to determine the effects of five traditional herbicides containing different active ingredients compared with mechanical hoeing for weed control on seed yield components, seed oil content, and fatty acid composition in sunflower. Field experiments were conducted in the sunflower growing seasons of 2014 and 2015 on farmer fields in Karamusul village of Lüleburgaz, Kırklareli, located in the Northwest of Turkey (40°24' N, 27021 E and elevation 46 m). Pre-plant herbicide Bonoflan WG with benfluralin, pre-emergence herbicide Stomp®Extra with pendimethalin, and postemergence herbicides Challenge600 with aclonifen and Targa Super with quizalofop-p-ethyl active were applied on non-Clearfield sunflower hybrids (P64LL05--Linoleic and P64H34--High oleic) while post-emergence herbicide Intervix®Pro with imazamox was applied on Clearfield hybrids (LG5542CL-Linoleic and Colombi--High oleic). In the results, the year effects were statistically significant on plant height, head diameter, number of days from planting to 50% flowering, and percentage of stearic acid of Clearfield cultivars while it was significant on plant height, head diameter, stem diameter, 1000 seed weight, number of days from planting to 50% flowering, seed yield, seed oil content, percentage of oleic and linoleic acids of non-Clearfield cultivars. The effect of genotype was significant for all seed yield and oil components except seed weight and seed yield for both groups' cultivars. Intervix®Pro caused significant decreases in plant height, stem diameter, and percentage of stearic acid. Stomp®Extra decreased the number of days from planting to 50% flowering. Challenge 600 had a negative effect on the seed oil content of P64H34 in 2015. There was no significant difference between herbicide applications and mechanical hoeing for seed yields except for increasing seed yield of P64H34 by Bonaflan WG in 2015. For all herbicide applications, residue in seeds was not exceeded international acceptable limits. According to the results, herbicides especially post-emergence applications under stress conditions can adversely affect agronomic yield and seed oil components in sunflower. [ABSTRACT FROM AUTHOR]

Maritime pine (Pinus pinaster Ait.) is a fast-growing pine species of the western Mediterranean Basin with important ecological (e.g., site restoration), economic (e.g., wood production), and social (e.g., recreation) values. Due to global climate change, the growing incidence of drought and wildfires challenges the distribution and growth of maritime pine. Mechanical site preparation (SP) either alone or integrated with chemical weed control can enhance site conditions for conifer seedlings, specifically by improving the physical and chemical condition of the soil and eliminating weeds. The study was established in the eastern Marmara Region of Turkey and included various SP techniques and cultural treatments (CT) of differing intensity applied in a factorial design before the plantation of one-year-old maritime pine seedlings. The SP treatments included raking by a bulldozer (SPB), raking by a bulldozer and then spraying with 1%-(v:v) glyphosate (SPH), and raking by a bulldozer followed by the broadcasting of the subsoil via bulldozer (SPS), the latter being the standard and the most intensive forest management SP treatment. The CT included various combinations of hoeing and foliar applications of glyphosate after planting. The SPH treatment was the overall best SP treatment in terms of seedling performance and physical and chemical soil properties at one and two YAT. The most intensive treatment (SPS) resulted in significantly reduced seedling growth, survival, and deterioration of physical and chemical soil properties, especially soil organic matter and nutrients. Hoeing in a 1-m radius around seedlings one year after planting (i.e. once during the experiment) (H1) significantly improved seedling survival and vigor compared to the control (H0). No additional gain in seedling survival or growth occurred with more intensive CT combinations. In summary, hoeing at the end of the first summer (H1) following the SPH is recommended for enhanced early seedling performance and soil productivity. [ABSTRACT FROM AUTHOR]